1. Field of the Invention
The present invention relates to a memory system which can have a large area and enables high-speed read/write operations to be performed.
2. Description of the Related Art
Recently, a thin-film transistor memory which can be formed on an insulative substrate such as a glass substrate has been developed. Examples of such a thin-film transistor memory are shown in U.S. patent application Ser. Nos. 07/427,041, 07/427,252 and 07/467,736 filed by the same applicant as the present application. This type of memory can be used as an electrically programmable non-volatile memory. Compared to a conventional MNOS (metal-nitride-oxide semiconductor) type memory or a floating-gate type EEPROM (electrically erasable programmable read-only memory), the manufacture of the thin-film transistor memory is easier and the area of this memory can be increased.
However, the thin-film transistor memory has such a problem that the access speed of this memory is lower than that of a widely used DRAM, etc.